Tier 2 — strong

Potential Clinical Benefits of Quercetin in the Early Stage of COVID-19: Results of a Second, Pilot, Randomized, Controlled and Open-Label Clinical Trial

Francesco Di Pierro, Somia Iqtadar, Amjad Khan, Sami Ullah Mumtaz, Mohsin Masud Chaudhry, Alexander Bertuccioli, Giuseppe Derosa, Pamela Maffioli, Stefano Togni, Antonella Riva, Pietro Allegrini, Saeed Khan
International journal of general medicine 2021 14:2807-2816

Bibliography

PubMed
PMID 34194240
PubMed Central
PMC8238537
DOI
10.2147/IJGM.S318949
Funding
Funding was not specified in the indexed record or the disclosure metadata available for this entry.
Competing interests
Reported disclosure: FDP belongs to the Scientific Board of Pharmextracta. AB is a Pharmextracta consultant. PA, ST and AR belong to the Scientific Board of Indena. ST & PA are employees of Indena SpA, producer of Quercetin Phytosome (ingredient used in the trial). AR reports a patent WO2019016146A1 pending. The other authors do not claim possible conflicts of interest.

Study snapshot

DesignRandomized open-label interim pilot report
ModelHuman intervention research
Sample42 COVID-19 outpatients; 21 per group
InterventionQuercetin Phytosome plus usual care versus usual care
Duration2 weeks
EndpointsSymptoms and quality of life

What the study showed, in plain terms

Published in 2021, this source examined immunity and respiratory health. Design: Randomized open-label interim pilot report. Sample/model: 42 COVID-19 outpatients; 21 per group. The exposure or intervention was Quercetin Phytosome plus usual care versus usual care. Follow-up or treatment period: 2 weeks.

Early viral-test conversion and symptom measures favored the supplement group.

Interim cohort from the program later reported in PMID 36712674. It is not an independent replication of the final report.

Continue with Quercetin Data Center

For topic-level interpretation, read Quercetin for Immune Health, Colds and COVID-19. This is a related guide; the citation panel separately identifies articles that directly cite this paper.

Key findings

  • Early viral-test conversion and symptom measures favored the supplement group.
  • The recorded outcome domains were Symptoms and quality of life.
  • The result applies to the tested exposure: Quercetin Phytosome plus usual care versus usual care; 2 weeks.

What this study can and cannot tell us

  • Interim cohort from the program later reported in PMID 36712674. It is not an independent replication of the final report.
  • Without a sufficiently blinded concurrent control, time effects, expectations, co-interventions and regression toward the mean can explain part of an apparent improvement.
  • Companion or correction records are linked below. They should not be counted automatically as independent replications; see the individual source notes for the relationship.
  • Source basis: Source check: accessible full text and indexed metadata. Missing method details, funding information or participant denominators are not inferred.

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Citation network

Articles citing this research paper

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Dr. Khaled Mahmoud, MBBChCritical Care Medicine, Longevity Science & Editorial Direction Dr. Amr Yasser, PhDCardiometabolic, Musculoskeletal, Gut & Bioavailability Dr. Abdulla Mostafa, PhDCellular Senescence, Neurological, Mitochondrial & Brain-Ageing Biology